1. Field of the Invention
The invention relates generally to improvements in agricultural harvesters for picking up nut produce and entrained orchard debris from windrows, and then separating the debris from the nuts so the latter can be further processed for storage and consumption. More particularly, the invention disclosed herein includes a harvester having three discrete but serially interconnected apparatus stages, each stage having components uniquely adapted for rapid and effective nut pickup and debris separating processes.
2. Description of the Prior Art
U.S. Pat. No. 2,916,868, granted to Ramacher et al., discloses a Nut Windrower. After nuts have fallen to the floor of an orchard, this device is driven through the orchard to sweep the nuts and other material on the orchard floor into elongated windrows, centrally positioned between rows of trees. At the time of harvest, an entire growing season of debris has collected on the orchard floor, making the composition of the windrows a random collection of nuts, leaves, twigs, clods, and the like. To complete this phase of the harvest, the windrows must then be picked up from the orchard floor, and the nuts separated from all of the aforesaid debris.
For that purpose, the Nut Harvester shown in U.S. Pat. No. 3,182,437, issued to Ramacher et al., was developed. The device disclosed in the '437 patent includes pickup means to lift material from windrows and deposit it on an endless conveyor 18. The material is transported and then deposited upon a screen conveyor 21, having openings designed to pass small pebbles and clods, but to retain almonds or other harvested nuts. At the other end of the screen conveyor is a pickup station including intake nozzles 37 and 38. Air flow through the nozzles entrains the nuts and leaves behind the heavier debris material. A vortical air separator 59 acts further to remove lighter debris which may still remain traveling with the nuts. As shown in FIG. 3, substantially only nuts pass by gravity to the bottom of separator 59, to be delivered eventually to an inclined chain conveyor 101.
Another design for harvesting nuts is illustrated in Harvester Pickup, made the subject of U.S. Pat. No. 3,872,657, granted to Ramacher, et al. This arrangement uses a primary brush and a counter-rotating secondary brush to pick up the material from the orchard floor, previously swept into windrows. The materials are hurled into a reflecting panel and dropped onto the lower end of a primary conveyor. A stream of air passes over the primary conveyor, removing lighter material and discharging it into the atmosphere. The remaining heavier material is discharged off the upper end of the primary conveyor into a vertically extending separator column. An upwardly extending draft of air passing through the column, acts upon lighter, irregularly shaped objects and discharges them into the atmosphere. Heavier, more uniformly shaped objects, namely, the nuts, pass downwardly, and are deposited onto an inclined secondary conveyor, and eventually into a collection bin, at the rear end of the harvester.
A single stage Trash Separator For Nut Harvester is taught in U.S. Pat. No. 4,642,977, issued to Ramacher. As shown most clearly in FIG. 3, primary and secondary counter-rotating reels 29 and 32, pick up the nuts and debris and tosses them upwardly. A tertiary pick-up reel 36 assists in keeping the material suspended as it enters the volume of a plenum 23. A chain conveyor 39 extends from the lower end to the upper end of plenum 23. A suction fan 49 has an inlet 54 in communication with a suction tube 56 which spans an upper portion of the plenum. The suction fan 49 also includes an outlet that discharges directly to the atmosphere. Screens 68 are provided on either side of the lower end of plenum 23. In a primary separation zone 66, air is sucked in through the openings in the screen, to engage leaves and other light debris. This debris is discharged by the fan. Gravity tends to make the remainder of the material fall onto the lower end of the conveyor belt 39. As the blanket of material passes up the conveyor, it reaches an area where the vacuum builds, causing a strong updraft which lifts the more aerodynamically responsive trash, but allows the nuts to rejoin or remain on the conveyor. The nuts pass upwardly on the conveyor, past a quiescent zone 77, and eventually into a storage bin 50.
U.S. Pat. No. 5,001,893, issued to Stanley, et al., discloses a Tractor Powered Nut Harvester. This harvester uses a suction fan and a housing mounted at the center of the front end of the harvester frame. Attached to the fan housing and extending rearwardly therefrom is an elongated vacuum chamber. The rear end of the vacuum chamber is in communication with a debris separation chamber. A rotary pickup mechanism deposits the windrow material onto the lower end of an upwardly inclined crop pick-up conveyor, adjacent the ground. The upper end of the crop-pickup conveyor deposits material onto the lower end of an upwardly inclined dirt removal conveyor. Debris drops through these two conveyors, as the material progresses rearwardly through the harvester. The upper end of the dirt removal conveyor is located within the debris separation chamber, and deposits material onto the lower end of an upwardly inclined off-load elevator. The lighter and more irregularly shaped debris is captured by the vacuum within the debris separation chamber, and drawn through the vacuum chamber, eventually to be discharged into the air.
In contrast to the above-discussed prior art, it is an object herein to provide a nut harvester having three separate but operationally related mechanisms, to pick up and clean windowed nut product.
It is a further object herein to provide a nut harvester having a rotary drum cleaner between a nut pickup apparatus and a tandem conveyor belt elevator with a vacuum cleaning fan.
It is yet a further object herein to provide a nut harvester with a rotary drum cleaner using the combination of tumbling action, size segregating slots, and gravity, to remove a high percentage of the debris entrained with the nuts.
It is another object herein to minimize the size and power of the vacuum cleaning fan used to remove debris from the tandem conveyor belt elevator in a nut harvester, to reduce the amount of dust and particulate matter discharged by the harvester into the ambient air.
These and other objects will become apparent in the specification and the detailed description of the preferred embodiment, to follow.